rates of reaction

Question 1

What is Particle theory

Answer 1

• The idea that all matter is made up of tiny particles, and they are in constant motion. Temperature affects the speed of particles - the higher the temperature, the more kinetic energy the particles have.

Question 2

What is Collision theory

Answer 2

• The idea that two or more reactants must collide with sufficient force (energy) and at the correct orientation. The minimum amount of energy required for a chemical reaction = activation energy.

Question 3

Factors affecting rates of reaction

- temperature

Answer 3

raising temperature causes particles to move quicker, and with more energy. This increases chances of a successful collision – which is required for a chemical reaction to occur.

Question 4

Factors affecting rates of reaction

- concentration

Answer 4

increasing concentration means there are more particles and they are closer together, so there is a higher chance of collision.

Question 5

Factors affecting rates of reaction

- surface area

Answer 5

when a solid reactant is broken into smaller pieces, the surface area increases because more particles are exposed, which means more particles can collide.

Question 6

Factors affecting rates of reaction

- catalysts

Answer 6

chemicals that speed up the rate of reaction but are not used up in the reaction. Some provide a specific site for collisions to occur, others lower the activation energy.